Thanks for your explanation,

maybe you know how to convert this to VFP,
This is a VB sample of the code that does the trick

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Declare Function Shell_NotifyIcon Lib "shell32" Alias "Shell_NotifyIconA" (ByVal dwMessage As Long, pnid As NOTIFYICONDATA) As Boolean
Public Declare Function SetForegroundWindow Lib "user32" (ByVal hwnd As Long) As Long

Public Const WM_LBUTTONDBLCLICK = &H203
Public Const WM_RBUTTONUP = &H205
Public Const WM_MOUSEMOVE = &H200
Public Const NIM_ADD = &H0
Public Const NIM_MODIFY = &H1
Public Const NIM_DELETE = &H2
Public Const NIF_MESSAGE = &H1
Public Const NIF_ICON = &H2
Public Const NIF_TIP = &H4

Public CIAsystray As NOTIFYICONDATA

Public Type NOTIFYICONDATA
cbSize As Long
hwnd As Long
uId As Long
uFlags As Long
ucallbackMessage As Long
hIcon As Long
szTip As String * 64
End Type

Public Sub SystemTrayAddIcon(Form As Form)
CIAsystray.cbSize = Len(CIAsystray)
CIAsystray.hwnd = Form.hwnd
CIAsystray.uId = vbNull
CIAsystray.uFlags = NIF_ICON Or NIF_TIP Or NIF_MESSAGE
CIAsystray.ucallbackMessage = WM_MOUSEMOVE
CIAsystray.hIcon = Form.Icon
CIAsystray.szTip = Form.Caption & vbNullChar
Call Shell_NotifyIcon(NIM_ADD, CIAsystray)

App.TaskVisible = False
Form.Hide
End Sub
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Many thanks
Jacques Herweijer